Acid-resistant packing



' No Drawing.

ane-.11.... a, 1929-.-

UNITED STATES- PATENT-lorries.-

WALTER namrnnsrnaucn. or rALIsAnE, NEW JERSEY, .ASSIGNOR .ro mnrarasrlcme or mnsEY'crrY, NEW JERSEY, A ooarona'rron or NEW JERSEY.

ncrp-rmsrsra rir rack-me.

This invention relates to chemical resistant 'packings and is hereindisclosed as embodied may be present insmall quantity onlyso that inpackings especially adapted for stufling boxes in which acidssuch assulphuric, nitric,- hydrochloric, citric, acetic, and tartaric come intocontact-with the packing. According to the" present invention thepacking includes it mainly is present as "a coating on the metal andasbestos and serves to hold them together and also serves to bind tothese any solid lubricant present. Preferably the packing also, includesa solid lubricant such as graphite.

- By observing the proper order of mixing -and using metal in asuitablef orm it is possible to prepare apackingwhich will contain a.large proportionof metal in such form that 2 it will not extrude throughthe clearance spaces between the fixed arts and moving parts of astufling box. uchia-packing is very eflicient, having ,lon li eflicientof frictions The following has been I a satisfactory packing from everypoint of view for attainmgsuch and other ends-z 75 pounds of lead:containing one-half of one per cent. of antimonywas mixed in'an -Abbemixer with 4' pounds of long, carded asbestos fibre to disintegrate theclumps of the fibre. The lead was 1n the form of small -.pieces, hereincalled chips, largely to inch long and mostly under 1 inch wide, Theasbestos was Mapleleaf Crude v8n Fibre Corporation, A. T. asbestos,varying from about 3 mm. in length and 0.25 mm. in diameter, to about 7mm. in length and 1.5 mm. in diameter. The asbestos wasfirst put througha picker having gripping feed rolls which delivered the fibreto aspike-covered rapidly revolving cylinder which had a disintegratingandcarding efiect The mixer had two concentric horizontal {shafts eachcarrying two blades working in a semicircular trough and rotatingiinopposite diIGCtlOIlS so as to feed'the material toward the center whilestirringand mixin-g it.

Application filed Ju1y 26,

foun

1924. Serial No. 728,369.

Afterethe asbestos was disintegrated and i pounds of Dixons .#2 flakegraphite.- The whole was then thoroughly mixed to produce thefinalpacking.

The final product of this procedure was a sulphuric acid resistantpacking. It was largely a fairly hard lumpy material in masses varyingfrom a quarter to a half-inch or even an inch across, in which thegraphite appeared for the most part'closely bound either to the fibreand/or as a thin. coating on the metaL; In some of the larger lumps themetal chips were closely packed. together, matted together. was in theform of loose agglomerated granules. The fibre was almost as closelybound.

A little of the graphite together as were the metal chips, and granulesof graphite clung to projecting fibres. Although the above descriptionis limited to-a packingresistant to. sulphuric acid, the invention is inno wise restricted thereto.

Packings resistant to variousother'acids mayv also be produced and areintended to be'em-- bracedby this invention. To produce apackingresistant to .any particular acid, it' is essential that the metallicingredient of the packing be resistant to that particular acid. Thus, ifa packing were to be used where it' would contact with nitric,hydrochloric, fruit acids or acids produced by fermentation, themetallic ingredients should be aluminum, copper or' tin respectively.The following illustrates a few of the specific examples of packingsresistant to various acids: J Peaking resistant to fruit acids of acidsgiroduced by fgrmentatz'on.

4 lbs. carded asbestos fibersa 13 lbs. oily material (3 lbs. tristearimcon- I taining less .,5 free fatty acid and mixed with 10 lbs. ofparaflin) 10 lbs. Dixons N0. 2 flake graphite. I

so 1bs. Dixons No. 2 flake graphite.

resistant to hydrochloric acid.

73 lbs. 4: lbs. 10 lbs.

cop r (annealed).

car ed asbestos fibers.

oilymaterial comprising 1 lbs. parowax which has been previously v mixedwith 3 lbs. C-706 oil.

10 lbs. Dixons No. Q'flake graphite.

Packzhig resistant to nitric acid.

55 lbs. aluminum.

lbs. carded asbestos fibers. lbs. parowax.

'To pack stufling boxes, the packing is heated to bring it into plasticform, and then asbestos, both thoroughly coated wit-ha pethe stuffingbox is packed.

Having thus described certain embodiments of the invention, what isclaimed is,

-1.An acid-resistant packing consisting largel of lead particles, andalso'containing as estos, both thoroughly coated with an .a graphiteacid-resisting Waxy material, coating on the lead and asbestos, and alsocontaining other graphite' v 2. An acid-reslstant packing consistinglargely of lead particles, and also containing asbestosfiaoth thoroughlycoated with a small quantity of an acid-resisting waxy material,

a graphite coating on the lead and asbestos, and also containing othergraphite.

3. An acid-resistant packing consisting largely of lead particles, andalso containing troleum wax, agraphite coating on the lead and asbestos,and also containing I other graphite.

4. An acid-resistant packing consisting largely of lead particles, andalso containing asbestosfboth thoroughly coated withparaflin wax, agraphite coating on the'lead v and asbestos and palso containing othergraphite.

5. An acid-resistant packing consisting largely of lead particles, andalso containing asbestos, both thoroughly coated with a small quantityofparatfin wax, a graphite coating v on the lead and asbestos, and alsocontaining 'other' graphite.

6. An acid-resistant packing containing about 75% of lead particles,about 4% oi asbestos fibre, about 10% of paraflin wax k coating the leadand asbestos, and about 11% of graphite, the packing being in the formof lumps. V

7. A packing material consisting largely of lumpy aggomera tes ofgraphite-coated lead bound togethenwith fibre, and other which it comesin contact in its intended use. and asbestos, both coated with anacid-resist mg waxy material, and graphite, said graphite coating themetal particles andasbestos and also being presentin'the form of looseagglomerated particles. I u

10. An acid-resistant packing-comprising metal particles resistant tothe acid with asbestos, an acid-resisting waxy material, and

whichit comes in contact in itsintended use,-

graphite, sa i d graphite being-present in an amount inexcess of thatrequired to coat the I metal particlesand asbestos. In testimonywhereoflI have-aflixed my signature to this specification.

'WALIER BA UTENSTRAUCH;

